Walter Montego: The Emperor is a royal piece (it can be substituted for the queen during the setup phase of the game, prior to piece movement phase); it has king movement plus the ability to move 2 squares vertically. Visualize the king castling in the standard game--it moves 2 squares horizontally. During the Italian domination of the old game, up until the late 1800s, the castling rules were more flexible, allowing the king to move several squares in combination with the rook. Prior to this, the king could move independently of the rook once in a game 2 squares horizontally, vertically, or diagonally, and take the rook with him as a personal guard. This Emperor is imitative of an earlier rule. In this particular case, the "King" can move vertically 2 squares as well as horizontally 2 squares, in the case of castling. That is a salute to the game in a more original, earlier form. Making this kind of substitution in the prelude phase allows for a tandem-ruler game with more than one target, or a switching of a targeted side, so as to reverse the weak-pawn from kingside to queenside. Tactically, you may want to hand your opponent a mental jab--"now let's see if you can adjust your pattern recognition to attack me on this side".